I think it's opening a new can of worm, as it implies selecting embryos that have the characteristics that you want... which makes you wonder what happens to the rest.
I mean, if you could just pick before the embryos are conceived, why not... but the way it works, you do in vitro fertilization, then you check the embryos to see what characteristics they have. I don't know if your question was hypothetical, but it's already possible to know the sex from an embryo... so yeah I can see how you could eventually find the rest too (no idea how advanced science is with that). And you'd be able to choose the embryo you want.
It just seems really wrong to me. Don't get me wrong, I don't consider embryos life, or I wouldn't be able to sleep considering we've lost over 10 of them, and I know that most of them usually just die anyway, but still.